YAC 1.2.0: An extendable coupling software for Earth system modelling
Abstract. A light-weight software framework has been developed as a library to realise the coupling of Earth system model components. The software provides a parallelised 2-dimensional neighbourhood search, interpolation, and communication for the coupling between any two model components. The software offers flexible coupling of physical fields defined on regular and irregular grids on the sphere without a priori assumptions about the particular grid structure or grid element types. All supported grids can be combined with any of the supported interpolations. We describe our approach and provide an overview about some of the algorithms we are using and the implemented functionality. The parallel performance is examined with a set of realistic use cases. The coupling software is now used for the coupling of the model components in the Icosahedral nonhydrostatic (ICON) general circulation model.